ive got a surplus of 4550's is why i was using them. why would i emulate a shift register? if my pic is just receiving data and processing it.
note that my pic will be replacing this whole board, so the serial data coming out of the main unit to this board should be a 5v data i would think.
also the use of the 4550 allows me to use the chip for other things too not just for a display. i also may want to interface a pc to this to get the data too so the usb will come in handy there.